Arsenal act as if they have their heart set on failure. They pursue it relentlessly and, on Sunday, achieved disappointment just when it seemed that a win over Liverpool was inescapable. With his last dregs of energy Emmanuel Eboué reached Lucas Leiva to ensure the foul was committed a moment before the midfielder would have left the penalty area. Dirk Kuyt's spot kick then secured the 1-1 draw.

The aftermath was predictable, with Arsène Wenger disputing the award of the penalty and the amount of stoppa ge time. It made him appear self-deluding when the grave flaws had all lain within the Arsenal line-up. This is a manager who is not at risk of the sack, but the standard he once set has slipped.

There are fans who believe the eccentric fallibility epitomised by Eboué's actions now clings to Arsenal. Birmingham City's winner over them in the League Cup final was a comparable absurdity.

Of late, the side has been experimenting with drabness, as in the goalless draws at home to Blackburn Rovers and Sunderland.

Such days should be less tolerable than ever for Arsenal and it is the mighty efforts of Wenger himself in earlier times that make disappointment so intense. At present there is no vivacity and spectators are disgruntled while their side are being outscored by the league leaders, Manchester United. Neutrals are deflated, too, since any element of drama about the outcome of the title race is diminishing.

A thorough upgrade of the Arsenal squad ought to have taken place. As it is, the prolonged injury to one centre-half, Thomas Vermaelen, has done terrible harm and there is no convincing goalkeeper on the premises. Given those circumstances, Wenger could almost congratulate himself on doing rather well, but Arsenal have the means to buy footballers of a greater calibre. While discussion of the club's finances can become complex, it is always a key talent for a manager to extract funds from the board.

Expensive as the construction of the Emirates was, the ensuing revenue is so vast that even Chelsea's owner Roman Abramovich may be consumed by envy. The income this season would have been greater still had the side not come second in their Champions League group and so put themselves in the path of Barcelona.

It is unlikely for the moment that anyone will be commissioning a contemporary version of the old "Arsène Knows" banner. Perhaps the manager has grown wary of money since spending rather a lot for, say, José Antonio Reyes and, on the present scene, Andrey Arshavin. The current Arsenal line-up, which have taken full points from just 10 of their 17 home games, fails to encourage any faith that a low-profile approach will set them above all rivals.

Robin van Persie has 17 goals for the season but injuries have restricted him to 13 starts in the league and neither Maroaune Chamakh nor Nicklas Bendtner appears a credible alternative. Wenger's penchant for coming up with inspired signings at modest cost has been on the wane. Some fans draw unfavourable comparisons with United, who have found bargains in Javier Hernández and, as he matures, Rafael da Silva.

Wenger has had coups in former times and there is an irony that the manager's feats made possible the creation of the Emirates, only for him to struggle to take full advantage of the expanded income it generates. Stan Kroenke increased his stake to over 62% this month and while the American is not the sort to encourage a crude spree, it will be essential for him to tap the potential of the club to the full if his investment is to grow steeply.

This might have been a splendid year for Arsenal, but triumph now would call for renewed vigour on their part and a slump by United. Neither eventuality is anticipated. Should this campaign drift even further away from Wenger's control it may be recalled as the last grand opportunity to be missed by Arsenal in this period.

Improvement should be anticipated at Chelsea and Manchester City. By the same token, we are still to find out just what new owners can achieve at Liverpool when their first full season gets underway.

Arsenal could find that Eboué's foul on Lucas lingers in the memory as the epitome of opportunities wasted that may not come to them so readily in the seasons ahead.